Conventionally, in a Social Network Service (SNS) (alternatively, referred to as Social Media), a mention function (alternatively, referred to as a comment function) for transmitting a posting while designating a user by whom the sender wants the posting to be viewed.
According to a conventional example of a mention function (alternatively, referred to as a comment function) provided by a messaging service included in an SNS service, when a user name is input following “@”, the posting may be notified to a user account of the inputted user name.
However, conventional mention functions does not take into account a case in which contents are being transmitted and received in a group that includes three or more users.